Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017636 (glioblastoma)
 18,345 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cells from a human glioblastoma (TC 526) maintained in tissue culture for ten years had a mean membrane potential of 27 +/- 0.9 mV at an external potassium concentration [Ko] of 5.3 mM. When [Ko] was varied between 2.5 and 5.3 mM, membrane potential changes were close to those predicted by the Nernst equation. At higher [Ko], the Nernstian slope was approached only in the presence of 10(-5) M ouabain, which did not affect membrane potential at a [Ko] of 5.3 mM. An electrogenic sodium pump activated by high [Ko] could explain these findings; such a mechanism has been demonstrated in other tissues.
J Cell Physiol 1975 Dec
PMID:Relationship between membrane potential and external potassium in human glioblastoma cells in tissue culture. 121 2

Malignant tumors induce angiogenesis and modulation of microvasculature. Based on histologic and immunohistochemical analysis of human surgical material, we describe here the occurrence of glomeruloid structures in gastrointestinal carcinomas, and compare them with the microvasculature in inflammatory granulation tissue. The glomeruloid structures were composed of clusters of mutually fused capillaries with prominent swelling of endothelial cells and pericytes. They were thought to be specific for glioblastoma of the brain. The glomeruloid structures were observed juxtaposed to carcinoma nests in one-third of gastric carcinoma of intestinal type and colorectal carcinoma in the area of invasive growth beyond the muscularis mucosae. They were not observed in gastric carcinoma of diffuse type, intramucosal carcinoma, or inflammatory granulation tissue. The glomeruloid structures can be regarded as an extreme example of endothelial hyperplastic changes observed in cancer stroma. Our results suggested that glomeruloid structures can occur in carcinomas as vascular reaction, a mechanism different from that in inflammatory granulation tissues.
Jpn J Cancer Res 1992 Dec
PMID:Glomeruloid structures as vascular reaction in human gastrointestinal carcinoma. 128 9

Nucleolar organizer regions (NORs) correspond to the loops of DNA which encode the ribosomal RNA. Acid proteins related to NORs can be stained by the silver colloidal technique (AgNORs). Since the configurations of AgNORs may be related to the protein metabolism or the proliferative activity of the cell, we tried to evaluate the corelationship between the morphology of AgNOR and the histologic malignancy in astrocytic tumors. For the quantitative evaluation the histographic pattern of AgNORs was analysed. Twenty-seven surgical specimens of astrocytomas (astrocytoma; 7 Cases, anaplastic astrocytoma; 9 cases, glioblastoma; 11 cases) were examined. The average of the means of AgNOR count in astrocytoma, anaplastic astrocytoma, glioblastoma were 1.68, 1.85 and 2.76 respectively. The averages of standard deviations (S. D.) of AgNOR count were 0.87, 1.03 and 1.26, respectively. In those tumors, the AgNOR histograms were flattered and the means and S. D. increased significantly as the malignancy increased. We speculate that the increased number and variations of AgNOR count could be a reflection of phenotypic alterations of astrocytoma cells such as cellular anaplasia and pleomorphism.
No To Shinkei 1992 Dec
PMID:[The analysis of nuclear organizer regions of astrocytomas with various histologic malignancies]. 129 27

The receptor that interacts with the mammalian bombesin-related peptide neuromedin B (NMB) is ubiquitous in the gastrointestinal tract and central nervous system. However, little is known regarding its cellular mechanisms of action. This receptor has been recently cloned, sequenced, and stably transfected into BALB 3T3 fibroblasts, permitting detailed study of the pharmacology and coupled biological activities of this receptor. In the present study, we compare the ability of transfected receptors to alter cell function with that of receptors natively expressed in small numbers by the rat glioblastoma cell line C6. NMB inhibited binding of 125I-[D-Tyro]NMB with high affinity in transfected cells (Ki = 3.08 +/- 0.14 nM) and in C6 cells (Ki = 1.90 +/- 1.10 nM), whereas the bombesin-related agonists gastrin-releasing peptide (GRP) and [D-Phe6, D-Ala11, Leu14]bombesin(6-16) (GRP analogue) had 100- and 300-fold lower affinities, respectively, for NMB receptors in either cell type. For both cell systems, maximal binding was observed between 5 and 15 min at 22 degrees. Both cell types internalized NMB at similar rates, with > 70% of bound ligand being internalized by 60 min at 22 degrees. The nonhydrolyzable guanosine analogue guanosine 5'-(beta,gamma-imido)triphosphate was equipotent in causing a decrease in binding of 125I-[D-Tyro]NMB due to decreased receptor affinity in both cell types, without a change in receptor number, demonstrating that the NMB receptor remained coupled to a guanine nucleotide-binding protein in both native and transfected cells. In both cell systems, NMB increased inositol monophosphate, inositol bisphosphate, and inositol trisphosphate in a time-dependent fashion. Inositol phosphates were increased in a dose-dependent fashion, with similar half-maximal values being obtained for NMB in both cell types (transfected, 1.01 +/- 0.09 nM; C6, 2.09 +/- 0.15 nM) and for the GRP analogue (transfected, 1855 +/- 140 nM; C6, 2129 +/- 250 nM). NMB mobilized intracellular Ca2+ in both cell systems, and the dose-response curves were superimposible (EC50 for transfected, 0.10 +/- 0.08 nM; C6, 0.11 +/- 0.02 nM). These data demonstrate that activation of the receptor for NMB stimulates phospholipase C and increases intracellular Ca2+. These results also demonstrate that transfected and native NMB receptors behave similarly, suggesting that the transfected cell line will be useful in future studies investigating ligand-receptor interactions, as well as in molecular biological studies of the structure-function relationship of the receptor.
Mol Pharmacol 1992 Dec
PMID:Neuromedin B receptors retain functional expression when transfected into BALB 3T3 fibroblasts: analysis of binding, kinetics, stoichiometry, modulation by guanine nucleotide-binding proteins, and signal transduction and comparison with natively expressed receptors. 133 12

PCNA (proliferating cell nuclear antigen) is said to be present specifically in the nucleus of proliferating cells. The PCNA labeling index (PCNA LI) of astrocytic tumors was measured and compared with histological types or prognosis. The specimens from 44 patients were fixed in a 10% formalin solution, and embedded in paraffin. The 3 microns-sections were stained immunohistochemically with anti-PCNA monoclonal antibody (PCIO, Novocastra) using an ABC method. The percentage of PCNA-positive-cells was determined by counting 2000 cells, and identified as PCNA LI. All of the PCNA-positive-cells showed diffuse nucleoplasmic staining. The averages of PCNA LIs in each pathological type were calculated and evaluated statistically. Although differences in averages of PCNA LIs among pilocytic, gemistocytic, fibrillary astrocytoma were not significant, there was a significant difference between anaplastic astrocytoma and glioblastoma. The relationship between PCNA LIs and the prognoses for 43 patients was studied. Forty-three patients were classified into 3 groups (over 22%, 7 to less than 22%, and less than 7%) according to PCNA LIs. The survival data in the 3 groups were analyzed, and differed significantly in the survival rates. Furthermore, twenty-three patients of anaplastic astrocytoma and glioblastoma were classified into two groups (over 22% and less than 22%). Likewise, the two groups differed significantly. In summary, pathological type and prognosis were closely related to PCNA LI in astrocytic tumors. Therefore, we thought measurement of PCNA LI would make it more possible to analyze clinically the proliferating activity of astrocytic tumors, and to care for patients more effectively.
No Shinkei Geka 1992 Dec
PMID:[Measurement of PCNA labeling index in astrocytic tumors]. 136 56

alpha-Difluoromethylornithine (DFMO), an irreversible inhibitor of the polyamine biosynthetic enzyme ornithine decarboxylase, inhibits the growth of brain tumor cell lines and is undergoing clinical trials as a treatment for brain tumors. Platelet-derived growth factor (PDGF) is thought to regulate the growth and development of precursors of both normal and neoplastic astrocytic cells; calcium signaling is thought to play a role in the transduction of PDGF signals. Using laser fluorescence image cytometry, flow cytometry, and spectrofluorometry, we studied the effect of DFMO on the calcium signals induced by PDGF in A172 human glioblastoma cells. Four days of treatment with 5 mM DFMO substantially shortened PDGF-induced calcium signals. The effect was reversed more than 10 h but less than 24 h after putrescine treatment, even though polyamines were repleted 4 h after putrescine and spermidine were added. DFMO did not substantially affect intracellular calcium release or the timing of the opening and closing of plasma membrane calcium channels. These findings support the notion that calcium signaling may be a target for inhibitors of polyamine metabolism.
Cancer Res 1992 Dec 15
PMID:alpha-Difluoromethylornithine alters calcium signaling in platelet-derived growth factor-stimulated A172 brain tumor cells in culture. 145 66

B cells derived from peripheral-blood lymphocytes (PBL) and tumor-infiltrating lymphocytes (TIL) from a patient with a high serum antibody titer to autologous melanoma were transformed with Epstein-Barr virus (EBV) and evaluated for reactivity against autologous tumor. B cells producing antibody reactive with autologous tumor and unreactive with normal fibroblasts were detected both in TIL and in PBL. One cell line derived from PBL and another derived from TIL sustained production of tumor-reactive antibody for 10 weeks and over 15 months respectively. The cell line derived from PBL, 2D11, produced an antibody reactive with a trypsin-resistant antigen expressed on the cell membrane of autologous and allogeneic melanoma cell lines. The cell line derived from TIL, 1F6, produced an antibody reactive with a cell-surface glycoprotein expressed by 5 autologous melanoma cell lines derived from 5 different metastases and 16/19 allogeneic melanoma cell lines. 1F6 also showed reactivity with cell lines derived from a blue nevus, a congenital nevus, an astrocytoma, and 1/4 renal-cell carcinomas; but it was not reactive with 5 foreskin melanocyte cell lines, 2 normal fibroblast lines, 5 leukemia/lymphoma lines, 8 lung-cancer lines, 8 glioblastoma lines, or lines derived from 1 ovarian carcinoma, 1 colon carcinoma, 1 vulvar carcinoma, 1 fibrosarcoma, 1 murine melanoma, or 4 murine leukemia/lymphomas. We describe here an antibody that detects a new melanoma specificity obtained by EBV transformation of tumor-infiltrating B cells.
Int J Cancer 1992 Dec 02
PMID:Analysis of two human monoclonal antibodies against melanoma. 145 38

The aim of this study was to verify the tolerability and efficacy of therapeutic chemotherapy protocols, employing different combinations of cisplatin, carboplatin, etoposide and carmustine in primary glioblastoma patients. The purpose was focused on 2 end points: the response index to treatment, the TTP (tumor progression) and the ST (survival time). Eighty-four out of a group of 99 consecutive glioblastoma patients, entered this study. Patients were divided into 4 disparate treatment groups: (A) BCNU alone; (B) CDDP + VP-16; (C) CBDCA + BCNU; (D) CBDCA + BCNU + VP-16. The effectiveness and the TTP of the protocols differed, but differences were not statistically significant. Data concerning platinum treatment compare favorably with the best literature results. At 18 months more than half the carboplatin-treated patients are alive. Moreover these patients had a significantly longer ST than those treated with BCNU. We conclude that platinum-based chemotherapy has a beneficial effect on glial tumors.
Ital J Neurol Sci 1992 Dec
PMID:Carboplatin combined with carmustine and etoposide in the treatment of glioblastoma. 148 54

We have been studying the role of human cytomegalovirus (HCMV) as a potential cofactor in human immunodeficiency virus (HIV)-related disease. The clinical relevance of HCMV is highlighted by the fact that it is a principal viral pathogen in patients with AIDS and is known to infect the same cells as HIV. In this study, we focused on the molecular interactions between HIV and HCMV in human fibroblasts and in the human glioblastoma/astrocytoma-derived cell line U373 MG, cells which can be productively infected by both viruses. Because these cells are CD4-, we used HIV pseudotyped with a murine amphotropic retrovirus as described previously (D. H. Spector, E. Wade, D. A. Wright, V. Koval, C. Clark, D. Jaquish, and S. A. Spector, J. Virol. 64:2298-2308, 1990). Initial studies showed that when cells were preinfected with HIV (Ampho-1B) for 5 days and then superinfected with HCMV, HIV antigen production dropped significantly in the coinfected cells but continued to rise in cells infected with HIV (Ampho-1B) alone. HCMV production, however, was unaffected by the presence of HIV. Further analysis showed that HIV steady-state RNA levels and gag and env protein production were also inhibited in the presence of HCMV. The transcriptional inhibition of HIV was particularly surprising in view of the previous results of several other laboratories as well as our own that HCMV infection stimulates HIV long terminal repeat-chloramphenicol acetyltransferase (LTR-CAT) expression in transient expression assays. To investigate this further, we transfected the HIV LTR-CAT construct into either uninfected cells or cells which had been preinfected with HIV. The cells were infected with HCMV 24 h posttransfection and assayed for CAT gene expression at 48 h after HCMV infection. Although there was some stimulation of the LTR-CAT in cells that were dually infected by HIV and HCMV, it was 16-fold less than that in the cells infected only with HCMV. This suggests that in the presence of the HIV infection, the stimulation of the HIV LTR-CAT gene by HCMV is significantly reduced. Experiments with UV-irradiated HCMV and the HCMV DNA polymerase inhibitor ganciclovir showed that HCMV transcription is necessary for the reduction in HIV production to occur; however, replication of the HCMV genome or any events which take place after DNA replication are not necessary. These results, coupled with the observation that inhibition is usually first seen between 8 and 24 h after HCMV infection, suggest that an HCMV early protein is involved in repression of HIV.
J Virol 1991 Dec
PMID:Human cytomegalovirus inhibits human immunodeficiency virus replication in cells productively infected by both viruses. 165 86

An 87-year-old woman suffered from Alzheimer's disease diagnosed 6 years prior to her death. Autopsy showed in addition to far-advanced Alzheimer's disease, a large, partially necrotic glioblastoma occupying her right hippocampus. Occurrence of a glial neoplasm in Alzheimer's disease could well be coincidental, since both entities are fairly common in elderly individuals; it is however, uncommon for gliomas to centre on the hippocampus itself. For these reasons it is possible (although cannot be proven from a single case), that florid reactive gliosis commonly associated with Alzheimer's disease, may have played a role in eventually initiating neoplastic proliferation of astrocytes in this patient.
Neuropathol Appl Neurobiol 1991 Dec
PMID:Glioblastoma multiforme of the hippocampus in advanced Alzheimer's disease. 166 75


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